Cerebrospinal fluid is a clear, colorless fluid found in the brain and spinal cord. The collection of CSF is usually indicated when a pet shows clinical signs, such as seizures, incoordination, circling behavior, and neck or back pain, when no obvious cause is known. The veterinary pathologist will evaluate the sample for a total nucleated cell count, a red blood cell count, a total protein determination, and a concentration of the cells in the sample. The presence of bacteria or fungal organisms may be detected along with increased numbers of inflammatory cells, leading to a diagnosis of bacterial or fungal infection. Neoplastic cells may also be found, indicating an underlying tumor within the brain or spinal cord.

Bone marrow is the soft material found in the central core of many bones. Bone marrow is commonly collected and examined when abnormalities are found in the circulating blood. The pathologist’s report typically provides information about the health of the marrow, the types of cells present, whether abnormal cells are found, and other details that may help to explain the patient’s illness.

Bile acids are compounds that are made in the liver and stored in the gall bladder and help with digestion of foods. The bile acid test is a very useful test that helps to determine if the liver is working properly. An abnormal bile acid test result indicates there is a problem in the liver, but it does not provide information about the cause, severity, or reversibility of the problem. Further testing is required to investigate the problem.